Featured Research

from universities, journals, and other organizations

'Shotgun' method allows scientists to dissect cells' sugar coatings

Date:

December 6, 2010

Source:

Emory University

Summary:

Sugar molecules coat every cell in our bodies and play critical roles in development and disease, yet the components of these "glycans" have been difficult for scientists to study, because of their complexity. Researchers now have adapted gene chip microarray technology to the study of glycans, with an approach they call "shotgun glycomics," a new chemical method for attaching a fluorescent dye to glycans purified from cells. The individual glycans are separated into tiny spots fixed to glass slides.

Share This

Sugar molecules coat every cell in our bodies and play critical roles in development and disease, yet the components of these "glycans" have been difficult for scientists to study, because of their complexity.

Related Articles

Researchers at Emory University School of Medicine have adapted gene chip microarray technology to the study of glycans, with an approach they call "shotgun glycomics." The Emory team has developed a new chemical method for attaching a fluorescent dye to glycans purified from cells. The individual glycans are separated into tiny spots fixed to glass slides.

The approach is described in an article published this week in the journal Nature Methods.

"These slides separate and display all the glycans in the cell, so that we can test what sticks to them," says senior author David Smith, PhD, professor of biochemistry and director of the Glycomics Center at Emory University School of Medicine. "However, the structures of the glycans are unknown. This is why we use the word 'shotgun' to describe our quasi-random approach of studying them."

The research team was led by Smith, first author Xuezheng Song, PhD, assistant professor of biochemistry, and Richard Cummings, PhD, chair of the Department of Biochemistry and co-director of the Glycomics Center.

As a demonstration of the technique's utility, the team used it to identify a molecule recognized by self-reactive antibodies present in the blood of most patients with Lyme disease. Lyme disease is caused by infection with Borrelia bacteria after a tick bite, but severe cases have features of an autoimmune response, triggered by the immune system's reaction to the bacteria.

"Being able to analyze glycans in this way may lead to new diagnostics for human autoimmune disorders, and perhaps, therapies to cleanse the body of self-reactive antibodies or inhibit their pathological attack on cells," Cummings says.

Completely dissecting glycans' structures is more difficult, compared with proteins or DNA, because glycans form branched structures in which not every link is chemically the same. Scientists have estimated that cells contain hundreds or thousands of different glycans, which can be attached to proteins or lipids. When using the shotgun approach, if scientists find that proteins from the body -- antibodies or toxins, for example -- bind to one particular glycan spot, they can then go back to that spot and determine its entire sequence, sifting out important glycans from the thousands on the slide.

"The sugars present on glycoproteins and glycolipids can contribute decisively to these molecules' functions," says Pamela Marino, PhD, who oversees glycobiology grants at the National Institutes of Health's National Institute of General Medical Sciences (NIGMS). "Understanding what information is encoded in these sugars and how they facilitate interactions with other proteins has been a major road block in deciphering the molecular language of glycans. This study, which is funded through the NIGMS EUREKA program for high risk research, has now provided proof of principle for an extremely novel 'shotgun' approach to interpreting this glycan code, and allows for examination of the role of glycans in infection and immunity."

The Emory team applied shotgun glycomics to red blood cells, tumor cells and brain-derived lipids. Cummings says the technique could be used to look for distinct sugar molecules displayed by cancer cells, for example. Identifying cancer-specific glycans could similarly lead to diagnostic tools or therapies, he says.

"A slide displaying glycans from a given cell type can be thought of as a book in the library, with the entire library constituting the human glycome," he says.

More From ScienceDaily

More Plants & Animals News

Featured Research

Mar. 3, 2015 — While studying a ground-nesting bird population near El Reno, Okla., a research team found that stress during a severe weather outbreak of May 31, 2013, had manifested itself into malformations in ... full story

Mar. 3, 2015 — The 3-D printing scene, a growing favorite of do-it-yourselfers, has spread to the study of plasma physics. With a series of experiments, researchers have found that 3-D printers can be an important ... full story

Mar. 3, 2015 — Most people consume more salt than they need and therefore have a higher risk of heart disease and stroke, which are the two leading causes of death worldwide. But a new study reveals that dietary ... full story

Mar. 3, 2015 — By examining the forces that the segments of mosquito legs generate against a water surface, researchers have unraveled the mechanical logic that allows the mosquitoes to walk on water, which may ... full story

Mar. 3, 2015 — Pediatric otolaryngologists and surgeons are concerned with parents getting the wrong message regarding the safety/desirability of letting babies and young children eat peanuts to prevent them from ... full story

Mar. 3, 2015 — Researchers have developed a new way of rapidly screening yeasts that could help produce more sustainable biofuels. The new technique could also be a boon in the search for new ways of deriving ... full story

Mar. 3, 2015 — Similar to humans and animals, plants possess an innate immune system that protects them from invading pathogens. Molecular structures that only occur in pathogens enable their recognition and ... full story

Mar. 3, 2015 — For almost a century, scientists have been puzzled by a process that is crucial to much of the life in Earth's oceans: Why does calcium carbonate, the tough material of seashells and corals, ... full story

Mar. 3, 2015 — To simulate chimp behavior, scientists created a computer model based on equations normally used to describe the movement of atoms and molecules in a confined space. An interdisciplinary research ... full story

Featured Videos

Rare Goblin Shark Found in Australia

AFP (Mar. 3, 2015) — A goblin shark, a rare sea creature described as an &apos;alien of the deep&apos; is found off Australia and delivered to the Australian Museum in Sydney. Duration: 01:25
Video provided by AFP

Zookeepers Copy Animal Poses In Hilarious Viral Photos

Buzz60 (Mar. 2, 2015) — Zookeepers at the Symbio Wildlife Park in Helensburgh, Australia decided to take some of their favorite animal photos and recreate them by posing just like the animals. Jen Markham (@jenmarkham) has the story.
Video provided by Buzz60

Related Stories

June 18, 2013 — All our cells wear a coat of sugar molecules, so-called glycans. Researchers have now discovered that glycans rearrange water molecules over long distances. This may have an effect on how cells sense ... full story

Aug. 13, 2012 — Scientists have found that important and resourceful bacteria in the baby microbiome can ferret out nourishment from a previously unknown source, possibly helping at-risk infants break down ... full story

Mar. 26, 2012 — Escherichia coli – a bacteria considered the food safety bane of restaurateurs, grocers and consumers – is a friend. Biomolecular engineers have learned to use E. coli to produce sugar-modified ... full story

May 28, 2010 — Researchers have successfully attached imaging probes to glycans -- the sugar molecules that are abundant on the surfaces of living cells -- in the embryos of zebrafish less than seven hours after ... full story

ScienceDaily features breaking news and videos about the latest discoveries in health, technology, the environment, and more -- from major news services and leading universities, scientific journals, and research organizations.